1. Field of the Invention
The present invention relates to an implantable electrode line for electrostimulation and particularly to a device having the features claimed herein.
2. Description of the Related Art
Electrode lines of this type are used in particular in the field of cardiology and are used for transmitting pulses from implantable medical devices such as cardiac pacemakers, defibrillator/cardioverters, a combination of both, or any other device to the heart.
Such electrode lines are known from the related art and are sketched in FIG. 1. They comprise a proximal end (not shown in FIG. 1), a medial section 11, a distal section 12, and a distal end 13. The proximal end comprises a standardized plug, using which the electrical contact to an implantable medical device is produced.
The medial section 11 comprises a first dielectric outer envelope and at least one electrical conductor, which conducts the electrical pulse to the electrical stimulation and/or measurement means (110 and 130).
At least the proximal end and the medial section 11 have a lumen running in the longitudinal direction, through which a guide wire may be guided in order to be able to place the electrode line at the desired position in a blood vessel, for example.
Furthermore, stimulation and/or measurement means 110 are provided at the distal end of the medial section, which may deliver a stimulation pulse to the surrounding tissue and/or may record physiological measured values.
The distal section 12 adjoins the distal end of the medial section 11. This distal section 12 is constructed similarly to the medial section 11, namely having a second dielectric outer envelope and at least one electrical conductor for relaying an electrical pulse. The distal section does not have stimulation and/or measurement means, however. A lumen running in the longitudinal direction may also be located in this area.
The distal section 12 must have an increased flexibility, in order to be better guided through a blood vessel with its coils, for example. If there is no increased flexibility here, injuries may result during implanting of the electrode line or an electrode line may not be guided through curvy vessels—as exist in the heart area, for example.
In order to allow the flexibility, reducing the external diameter of the dielectric envelope of the distal section is known from the related art. This means the distal end having the stimulation and measurement means and the medial area project radially out of the external diameter of the distal section. The material tapering results in increased flexibility in this area. (See FIG. 1)
In the achievement of the object known from the related art, the problem is the loss of the isodiametry just described. Such an electrode line—like any other implantable device—grows into the tissue. Such undercuts grow in such a way that removal is no longer possible or is only possible with difficulty. For electrode lines, the problem additionally arises that the location at which the ingrowth occurs is not accessible.
If an electrode line is to be removed, the attempt is made to exert a tractive movement in the proximal direction from the proximal end. If the electrode has grown in at this undercut, non-isodiametric section of the distal section, in the simplest case, it may be more difficult to remove the electrode, but in the worst case this may result in injury at to the tissue or even in the distal end of the electrode line being torn off. Such injuries or tearing off such parts may result in grave, life endangering states for the patient.